<!doctype html>
<meta charset=utf-8>
<title>toBlob() reports the exception from its callback in the callback's global object</title>
<script src=../../../../resources/testharness.js></script>
<script src=../../../../resources/testharnessreport.js></script>
<iframe srcdoc="<canvas></canvas>"></iframe>
<iframe></iframe>
<iframe></iframe>
<script>
setup({ allow_uncaught_exception: true });

const onerrorCalls = [];
window.onerror = () => { onerrorCalls.push("top"); };
frames[0].onerror = () => { onerrorCalls.push("frame0"); };
frames[1].onerror = () => { onerrorCalls.push("frame1"); };
frames[2].onerror = () => { onerrorCalls.push("frame2"); };

async_test(t => {
  window.onload = t.step_func(() => {
    const canvas = frames[0].document.querySelector("canvas");
    canvas.toBlob(new frames[1].Function(`throw new parent.frames[2].Error("PASS");`));

    // Wait until at least one `onerror` fires.
    t.step_wait_func(() => onerrorCalls.length != 0);

    // Wait for 25ms more in case one other `onerror` fires.  This is inherently
    // flaky...
    t.step_timeout(() => {
      assert_array_equals(onerrorCalls, ["frame1"]);
      t.done();
    }, 25);
  });
});
</script>
